# Copyright 2017 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""This package facilitates HTTP/REST requests to the registry."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

from containerregistry.client import docker_creds
from containerregistry.client import docker_name
import httplib2


class BadStatusException(Exception):
  """Exceptions when an unexpected HTTP status is returned."""

  def __init__(self, resp, content):
    message = 'Response:\n{resp}\nContent:\n{content}'.format(
        resp=resp, content=content)
    super(BadStatusException, self).__init__(message)
    self._resp = resp
    self._content = content

  @property
  def resp(self):
    return self._resp

  @property
  def status(self):
    return self._resp.status

  @property
  def content(self):
    return self._content


# pylint: disable=invalid-name
def Request(transport,
            url,
            credentials,
            accepted_codes = None,
            body = None,
            content_type = None):
  """Wrapper containing much of the boilerplate REST logic for Registry calls.

  Args:
    transport: the HTTP transport to use for requesting url
    url: the URL to which to talk
    credentials: the source of the Authorization header
    accepted_codes: the list of acceptable http status codes
    body: the body to pass into the PUT request (or None for GET)
    content_type: the mime-type of the request (or None for JSON)

  Raises:
    BadStatusException: the status codes wasn't among the acceptable set.

  Returns:
    The response of the HTTP request, and its contents.
  """
  headers = {
      'content-type': content_type if content_type else 'application/json',
      'Authorization': credentials.Get(),
      'X-Docker-Token': 'true',
      'user-agent': docker_name.USER_AGENT,
  }
  resp, content = transport.request(
      url, 'PUT' if body else 'GET', body=body, headers=headers)

  if resp.status not in accepted_codes:
    # Use the content returned by GCR as the error message.
    raise BadStatusException(resp, content)

  return resp, content


def Scheme(endpoint):
  """Returns https scheme for all the endpoints except localhost."""
  if endpoint.startswith('localhost:'):
    return 'http'
  else:
    return 'https'